A vibration absorber provided for a drive shaft in a motor vehicle is known, for example, from DE 196 38 290 A1. Since the latter is not segmented, the later assembly of the vibration absorber is complicated because the shaft has to be detached at least at its one end in order to put the vibration absorber over it. It was found in practice that, due to tolerances in the production of the vehicle or of its drive components, it is frequently necessary to retrofit vibration absorbers. There is a basic demand for simplifying this retrofitting by the shaft or axis not having to be disassembled.
A vibration absorber that can be retrofitted in this manner is known from DE 43 35 766 A1. It comprises an inner part including two half-shells, which rest on the outer circumference of the rotating shaft, and a deformable spring member. An outer part serving as an inertial mass member is disposed so as to grip around the spring member. It consists of two segments respectively connected, at their one end, in an articulated manner, and which are clamped at their other end by means of a separate closing member. What is disadvantageous in this structure on the one hand is the fact that the closing member is formed as a separate component. In order to fasten the closing member, recesses are required in the outer part, which cause imbalances and must be compensated for elaborately, at least at high rotational speeds. In addition, the clamp can become detached due to the high centrifugal forces and in particular in the case of fatigue in the clamp, which is based, inter alia, on the fact that the clamp can drop off in the radial direction. Moreover, due to the separate closing member, an additional part is required which has a negative effect on the storage and transport costs. Moreover, a plurality of parts renders assembly more difficult, because the outer part first has to be compressed, in order to attach the clamp in the next step while the outer part is compressed. This demands a lot of skill on the part of the fitter. On the other hand, the articulated connection is disadvantageous in that it disadvantageously provides for recesses in the ideally rotation-symmetrical outer part because of the provision of pivotability; the recesses must be compensated for elaborately in order to avoid imbalances. In addition, a certain amount of space is required for assembly in order to be able to attach the folded-open outer part on the shaft or axis vertically in relation to the axis of rotation. As a rule, the drive shafts of a motor vehicle lack this space.
A torsion bar bearing is known from DE 690 00 203 T2 in which a relatively rigid frame of two opposite half-shells has ribs of resilient material on each of the insides of the half-shells. The half-shells are configured at their two ends in the circumferential direction with connecting members formed integrally therewith, in order to establish a mutual latching connection.
In view of the above drawbacks of the prior art, it is therefore the object of the present invention to provide an improved vibration absorber for clamping attachment to the outer circumference of a rotating shaft or axis, which enables an inexpensive, secure and simple attachment. This object is achieved with a vibration absorber as set forth in the independent claims. Advantageous embodiments are in each case the subject matter of the dependent claims.